The In Vitro Non-Tetramerizing ZapA I83E Mutant Is Unable to Recruit ZapB to the Division Plane In Vivo in Escherichia coli

• Published in: International journal of molecular sciences Vol. 21; no. 9
• Main Authors: Meiresonne, Nils Y, den Blaauwen, Tanneke
• Format: Journal Article
• Language: English
• Published: Switzerland 29.04.2020
• Subjects: Carrier Proteins - chemistry; Carrier Proteins - genetics; Carrier Proteins - metabolism; Cell Cycle Proteins - chemistry; Cell Cycle Proteins - genetics; Cell Cycle Proteins - metabolism; Cell Division - genetics; Escherichia coli - physiology; Escherichia coli Proteins - chemistry; Escherichia coli Proteins - genetics; Escherichia coli Proteins - metabolism; Mutation; Phenotype; Protein Binding; Protein Multimerization; Protein Transport; ter linkage; filamenting temperature-sensitive Z (FtsZ); MinC; Cell division; Z-associated protein A (ZapA); Z-associated protein B (ZapB)
• ISSN: 1422-0067

Bacterial cell division is guided by filamenting temperature-sensitive Z (FtsZ) treadmilling at midcell. FtsZ itself is regulated by FtsZ-associated proteins (Zaps) that couple it to different cellular processes. Z-associated protein A (ZapA) is known to enhance FtsZ bundling but also forms a synchronizing link with chromosome segregation through Z-associated protein B (ZapB) and bound MatP. ZapA likely exists as dimers and tetramers in the cell. Using a ZapA mutant that is only able to form dimers in vitro (ZapA ), this paper investigates the effects of ZapA multimerization state on its interaction partners and cell division. By employing fluorescence microscopy and Förster resonance energy transfer in vivo it was shown that ZapA is unable to complement a deletion strain and localizes diffusely through the cell but still interacts with FtsZ that is not part of the cell division machinery. The diffusely-localized ZapA is unable to recruit ZapB, which in its presence localizes unipolarly. Interestingly, the localization profiles of the chromosome and unipolar ZapB anticorrelate. The work presented here confirms previously reported in vitro effects of ZapA multimerization in vivo and places it in a broader context by revealing the strong implications for ZapB and chromosome localization and linkage.